Portable refrigerator device



3 Sheets-Sheet 1 6 672C@ T50re/z5ef2,

C T SORENSEN PORTABLE REFRIGERATOR DEVICE Filed March 1, 1937 May 6, 1941,

1 'I I I l I I I I I I I I I I I I I I I I I I I l I I i I Flled March 1, 1937 I@ C T SORENSEN PORTABLE REFRIGERATOR DEvIcE `May 6, 1941. c. T. som-:NSEN

PORTABLE REFRIGERATOR DEVICE 3 Sheets-Sheet 3 Filed March 1, 1937 fwefz: [Za/ence Torefzerz,

Patented May 6, 1941 UNITED STATES PATENT orslcs PGRTABLE REFRIGERATOR DEVICE `Clarence T. Sorensen, Belding, Mich.

Application March 1, 1937, Serial No. 128,373 9 claims. (o1. s2-120) The present invention is related to portable refrigerating devices of the type disclosed in my pend-ing application for Letters Patent of the United States filed July 10, 1936, Serial No. 89,900, noW Patent No. 2,184,322.

The refrigerator of the aforesaid application is of the intermittent absorption type, and the primary object of the present invention is the provision of simple and eliicient means for distilling off the ammonia from the absorbent during the heating cycle so as to insure a highly concentrated degree of the ammonia in the evaporator, and thereby accomplish a high degree of refrigeration during the absorbing or refrigerating cycle.

Furthermore, the invention seeks to provide a refrigerator of the type referred to wherein means are provided to prevent return to the generator-absorber, during the absorbing or refrigerating cycle, of such portion of the absorbent las may find its Way into the evaporator when fthe ammonia is driven over to the evaporator during the heating cycle. This accelerates the production of the requisite lovv temperature at the evaporator and expedites the refrigerating action of the apparatus.

A further object of the invention is to so construct the refrigerator that the evaporator may be more efficiently vented when it is desired to return the absorbent to the generator-absorber, thereby effectually clearing the evaporator of the absorbent that may go over to the evaporator and conditioning the latter for more effective action When the anhydrous ammonia reaches the same on the next heating cycle.

A furtherobject of the invention is to improve and simplify the construction 0f the refrigerator of my aforesaid application so as to render the same more compact land readily adaptable for use in automobile trailers and in other places of use Where but liimted space is available for accommodating the refrigerator. The present structure is so organized and its parts so related as to adapt the same admirably for the uses indicated.

Other objects and advantages of the invention Will appear as the nature of the improvements is better understood, the invention consisting substantially in the novel construction, combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and finally pointed out in the appended claims.

While the form of the invention made the basis of the present disclosure is believed to be a preferred embodiment thereof, and shows a practical adaptation of Ithe same to the uses and purposes forA which it is intended, it Will be understood that the present delineation is to be considered from an illustrative standpoint and not as imposing restriction or limitation upon the invention.

In the drawings:

Fig. 1 is a ftop plan view of a portable refrigerating device embodying the present invention;

Fig. 2 isV a vertical transverse sectional view thereof, as on the line 2-2, Fig. 1;

Fig. 3 is a side elevation, partly in section, of the device;

Fig. 4 is a face elevation of a refrigerator cabinet, preferablyfor use in an automobile trailer,

equipped With a portable refrigerator such as herein shown and described;

Fig. 5 is la transverse sectional view of such cabinet so equipped;

Fig. 6 is a sectional plan view, as on the line 6 3, Fig. 5.

Having reference novv in detail to the accompanying drawings, .the numeral Ill designates the generator-absorber of the type and construction disclosed in my pending application Serial No. 89,900. It includes an outer shell II, and in the bottom thereof there is provided an inner shell I2. The' latter is inset within the lower end of the outer shell II in order to provide a combustion chamber for a blue flame oil burner, and thereby to provide the source of heat for the generator-absorber,

A plurality of 'flues I3 extend from the inner shell I2 to the top of the outer shell II, these iiues being open at both ends, and thus passages are formed for the products of combustion ema-A nating from the blue-name oil burner referred to. The provision of the flues I3 lassists greatly in raising the temperature of the contents of the generator-absorber to the point Where the ammonia is given off from the absorbent.

The generator-absorber I0 is provided With a charging fitting I4 for the introduction to the generator-absorber of the absorbent and the refrigerant. Water is utilized as ,the former and ammonia as the latter.

The generator-absorber I0 also is provided with a safety device I5 so as to release excessive pressures Within the generator-asborber, should such pressures arise.

Generally speaking, rthe construction of the generator-absorber as described is that disclosed in my aforesaid application, and the details, therefore, need not be further recited.

It will be understood that when the generatorabsorber I is properly charged with the absorbent and fthe refrigerant, and before any heat is applied -to the generator-absorber, the liquid will lie at a certain high level within the generatorabsorber. This is indicated by the line A-A in Fig. 2. When the ammonia has been driven off under the influence of the heat, obviously the level of the liquid is lowered, and this low level is vindicated bythe line B-B in Fig. 2.

Arranged'at the top of the outer shell I I, and communicating with the interior thereof, is a relatively short gas pipe I6. The outer end of the pipe It is covered by an inverted cap I'I',l

which is of larger diameter than the diameter of the gas pipe I6, said cap II being spaced sufciently from the upper end of the pipe I6 so as to provide a clear passage between that pipeand the interior of the cap Il'. By the provision of the cap Il a barrier is presented to the ammonia gas `as it rises from the heated liquid contents of thegenerator-absorber Iii, and when sufcient pressure is lreached the gas isl forcedv downwardly to the lower end of the cap Il for discharge at thev lower edges thereof.

A gas dome Ifsurmounts the outer shell III of the generator-absorber, its lower edgesy being connected to the top of the shell Il'so as to provide a tight joint thereat, and said dome I3 encases the cap I-'I `and the 'gas pipe I6. Projectingwithin the gas dome I8 is the upper end of a drain pipe It9,. The purpose of the pipe I9 is to Ydrain .back into the generator-absorber surplus water which may pass into thexdome I8 with the ammonia gas. The extent to'which the upper `projecting end of the drain pipe I9` lies within the'dome I8 may vary. The primary purpose of projecting the end of the pipe I9' within sa'id dome is lto create aY ywater kseal within the dome the upper edge of the drain pipe I9 marking the level of the water of the seal; as indicated by the line C-C. Should this level rise `beyond that point the surplus water entersthe upper open end of the pipe I9 and passes back into the outer shell I I. ln thisconnection. it will be noted that the lower end' ofthe drain pipe I9 is at the lowest point of theV outer shell II so ,as to deeply seal the lower end of the drain pipe I9, the purpose of which will appear at a later point herein.

The dome I3 and its water seal serves as a rectifier or analyzer for the'ammonia gas as the 4gas enters through the pipe I6. Such water vapor as accompanies the gas vis trapped in the cap Il and is there oondensed,being caught by the'water within the dome I8 and, as previously indicated', when the water constituting the seal Vbecomes vexcessive the surplus thereof spills over into theupper end of the drain pipe I9 and is returned tothe liquid in the outer shell II.

Because of the water seal the gas likewise'is trapped in the cap Il, but when the pressure has reached the necessary degree the gas will be forced `down through the water of the seal, pass out'at the'lope'n lower' end of the cap, and rise through the water to the space above the level thereof and between such level and the topv of the dome I8. At this point the ammonia gas has been freed `of substantially all of the water which accompaniedvr the ksame into the dome I 9. The gas, therefore, is practically dry;

Leading upwardly from the gas dome I8 is a vapor delivery pipe 29. The :lower end of this pipe is in communication with the interior of the dome I8, and such gas .as accumulates within the dome I8 rises within the pipe 29 to be conveyed evaporator of the refrigerator.

thereby to a condenser, and ultimately to lind its way, when condensed to a liquid state, to the By referring to Fig. 2, it will be observed that the upper end of the vapor delivery pipe 29 is bent downwardly, and is received by a closed cylindrical sleeve 2I. Ihe sleeve 2! is of greater diameter than the diameter of the vapor delivery pipe 2G, thereby spacing the sides of the sleeve 2i from the sides of the upper end of the Vapor delivery pipe 29. The sleeve 2| constitutes a condenser, the extremity of the upper end of the pipe 29 being open and discharging at the lower end of the sleeve 2I. When, therefore, the hot ammonia gas is discharged from the end of the pipe 29 it contacts the cold temperature prevailing in the condenser sleeve. 2! and becomes liquied. Such of the absorbent as may be carried over with the hot gas in the vapor conveyed by the pipe 29 to the sleeve 2| also becomes liquied. The water, however, being of greater speciiicgravity than the ammonia, remainsat the bottom or lower end of the condenser 2|, while the ammonia rises to the top thereof, whence it is conveyed by a feed pipe 22 from the sleeve 2i to an evaporator 23. The evaporator 23 may be formed of any desired shape, but is generally cylindrical. So long as heat is applied to the generator-absorber I9 the ammonia gas will be generated and pass over to the evaporator 23 through the vapor delivery pipe 29, the condenser 2 I, and the feed pipe 22.

To provide the requisite low temperature for condensing the ammonia gas, the condenser sleeve ZI and the evaporator 23 are immersed in a body of cold water which may be contained in a vessel of sufficient capacity to receive the condenser sleeve and the evaporator. This immersion continues throughout the period that the generator-absorber is under fire, or the heating cycle attending the operation of the apparatus. During such `period a head of anhydrous ammonia builds up within the evaporator 23.

Extending from the evaporator 23 to the generator-absorber I9 is a vapor return pipe 24. The upper end of this pipe is in communication with the top of the evaporator 23 and is designed to receive the ammonia vapors which arise within the evaporator during the absorbing or refrigerating cycle. The lower end of the return pipe 24 passes downwardly through the gas dome I8 and also through the top of the outer shell II of the generator-absorber, its extremity being positioned within the generator-absorber at a point which is just below the low liquid level or line B-B. This location of the discharge end of the vapor return pipe 24 delivers the ammonia vapors beneath the level of the liquid contents of the generator-absorber, thus enabling the ammonia vapors to be re-absorbed by the liquid of the generator-absorber.

That the evaporator may be efficiently vented for returning the absorbent to the generatorabsorber, and also to provide rapid absorption as well as rapid circulation of the gas through vthe evaporator, a vent connection extends between the upper end of the condenser sleeve 2|, at which end a gas space is provided, and a high point on the vapor return pipe 2d. This connection generally is in the form of a pipe elbow 25 the upper end of which is connected to the bottom side of the vapor return pipe 2li, while its lower end is connected to the upper end of the condenser sleeve 2| so as to be in communication with the gas space at that point'. The effect of the vent connection 25 is to balance the pressure on the liquid in the condenser sleeve 2| with the pressure in the vapor return tube 24.

Reference has been made to the fact that in the heating cycle the condenser 2| and the evaporator 23 are immersed in a body of cold Water forthe purpose of condensing the ammonia vapors as they pass over from the generatorabsorber. It will be understood also that when the heating cycle has ceased, and the absorbing or refrigerating cycle is to commence, the condenser 2| and the evaporator 23 are removed from the water bath or cooling body and the generator-absorber is placed therein for the purpose'of cooling the generator-absorber. When this occurs the temperature within the generator-absorber is reduced, with a simultaneous reduction of pressure within the generatorabsorber. This sets up a violent boiling of the refrigerant in the evaporator 23, and causes the gases formed by such boiling to carry the latent heat back from the evaporator 23 through the vapor'return pipe 24 to the interior of the generator-absorber |0. With the generator-absorber removed from the cooling water the air contacting the surfaces of the generator-absorber and also flowing through the ues 3 thereof will continue to maintain the generator-absorber at a reduced temperature. As the refrigerating cycle continues the ammonia passes from the evaporator 23 back to the generator-absorber and becomes absorbed by the liquid therein, and this continues until the ammonia in the evaporator 23 has entirely evaporated.

In Figs. 4, 5 and 6 the application of the herein described refrigerator device is shown with respect to a refrigerator cabinet designed to be used with an automobile trailer. The cabinet, designated by the numeral 26, may be of any desired construction as constituting the presentday refrigerator, but is shown as embodying an upper food chamber 21 and a lower cupboard space 28. The open ends of the food chamber 21 and the cupboard space 28 are closed by a common door 29 which is suitably hinged at one of its side edges to the frame of the cabinet, as indicated at 30.

To accommodate the herein described refrigerating unit or device to the cabinet 28 the same may be fixed to or removably connected with the door 29 so as to move therewith, and thereby be introduced to and removed from the interior of the cabinet when the door is opened and closed. When so positioned on the door, and when the unit lies within the cabinet, the generatorabsorber I0 is within the cupboard space 28, while the evaporator 23 is within the food chamber 2'|, the vapor delivery tube 20 and the vapor return tube 24 passing upwardly through a suitable notch 3| formed in the partition between the cupboard space 28 and the food chamber 2l. The generator-absorber I0 is received by an arcuate supporting bracket 32 carried at the lower end of the inner face of the door 29, said bracket serving to position the refrigerating unit in vertical relation to the door 29 and to maintain the same sustained in such position.

In the operation of the herein described refrigerating device, a blue-flame burner having been placed beneath the generator-absorber i0, and the latter being charged with the requisite quantity of absorbent and refrigerant, the vapors arising from the boiling of the liquid pass upwardly through the gas pipe i6 and are discharged within the cap where, upon the rise of the requisite pressure due to the accumulation of the vapors within the cap, they are caused to pass downwardly through the water seal. In such passage such of the absorbent as accompanies the ammonia vapors is condensed, and the ammonia freed therefrom. The ammonia vapors rise through the water seal and pass into the vapor delivery pipe 20. This pipe conducts the ammonia vapors to the condenser sleeve 2|, and they are discharged from the pipe 20 into the lower end of the sleeve 2|. This lower end of the sleeve 2| acts as a sump. As the sleeve 2| and the evaporator 23 are immersed in the cooling Water, the ammonia vapors are condensed, and the liqui-d ammonia rises to the top of the water within the sleeve 2|. The ammonia thereupon passes through the feed pipe 22 to the evaporator 23 where the ammonia is collected and builds up into a head until the heating cycle is finished. At this time the liquid level Within the generator-absorber has fallen from the high level designated by the line A-A to the low level designated by the line B-B. At this low level, however, the lower ends of the drain pipe I9 and the vapor return pipe 24 are covered by the liquid of the generator-absorber and sealed by such liquid. The condenser 2| and the evaporator 23 now being removed from the cooling water bath, the generator-absorber l0 is placed in the latter and permitted to remain therein suciently long to effect its cooling, and thereby reduce the temperature and pressure conditions within the generator-absorber. When the latter conditions have been established the ammonia Within the evaporator 23 will evaporate, effecting a heat exchange between the evaporator and the condenser sleeve 2| and the surrounding air, and with the evaporator placed within the refrigerating compartment of a refrigerator cabinet, the temperature conditions of the compartment become lowered. The refrigerating effect of the evaporator 23 is manifested by a frosty deposit thereon.

As the ammonia continues to evaporate within the evaporator 23 the gases pass over through the 4vapor return pipe 24 and are conducted thereby to the interior of the generator-absorber I0 where they are discharged at the lower end of the pipe 24 within the absorbent which remains in the generator-absorber.

After the evaporator 23 has been emptied of the ammonia the refrigerating or absorbing cycle ceases, and this is evidenced by the defrosting of the evaporator.

Before the apparatus is subjected to the next heating cycle it is essential that such of the absorbent as may have passed over to the condenser 2 and which might remain in the evaporator 23, shall be returned to the generatorabsorber. To accomplish such return the device is positioned on its side so that the evaporator 23 and the condenser sleeve 2| may drain into the vapor-delivery pipe 28 and into the dome I8, thence through the drain pipe I9 into the generator-absorber. The gas space within the generator-absorber, being taken up by the liquid from the evaporator, is reduced, and this gas in turn must replace the liquid in the evaporator 23. The gas, therefore, passes through the bottom end of the vapor return pipe 24 into the evaporator 23, the vent connection 25 providing a vent for the condenser sleeve 2|, thereby permitting the return of the liquid.

Tests have established that at the end of the heating .cycle when the generator-absorber I0 is placed in the cooling bath to reduce the temperature and pressure inthe: generator-absorber, the f pressure drops from approximately 260 pounds to 38 pounds at the gauge in about three minutes, whereupon the evaporator'r 23 frosts, as previously stated. At this time the level of the liquid within the evaporator '23, ,the condenser sleeveiZI and the upper end of the vapor-delivery pipeiZ located in the sleeve 2 l, is approximately that indicated by the line D-D in Fig. 2. Were it not for the presence of the vent connection 25 the gas in the upper end of the sleeve 2l above the'level of the line D-D would be trapped and have no way of returning to the generator-absorber I0. Pressure of the gas, therefore, would force the liquid .upwardly within the upper end of the vapor-delivery pipe 20 and back to the generator-absorber. By use of the vent connection 25, however, the pressure is balanced when the sudden reduction referred to takes place. 'Ihe connection A25 also prevents slugs of the refrigerant below the line 'D-D being shot over tothe generator-absorber through the vapordelivery pipe 20, which, if fast enough, might causeV a syphonic action and return most, of the refrigerant before the absorbing or refrigerating cycle is completed. This condition particularly is avoided while the absorbing or refrigerating cycleV is in progress with the unit installed in an automobile trailer, and the latter is in motion over rough roads, hills and curves, subjecting the refrigerant to agitation.

I claim:

'1; In a refrigerating device of the class described, the combination with a generator-absorber, an evaporator, and a condenser in communication with said evaporator, of a vapor delivery pipe between the generator-absorber and the condenser, a vapor return pipe between the evaporator and the generator-absorber, and a connection between the vapor return pipe and the condenser for balancing the pressure 'in the vapor return pipe and the condenser.

2. Inra refrigerating device of the class described, the combination with a generator-absorber, an evaporator, and a condenser in communication with said evaporator, of a vapor delivery pipe between the generator-absorber and the condenser, a vapor return pipe between the evaporator and the generator-absorber, and a tubular connection between the vapor return pipe andk the condenser for balancing the pressure therein, the point of communication of said connection with said vapor return pipe being in a higher plane than its point of communication with the condenser.

3. In a refrigerating device of the class described, the combination with a generator-absorber, an evaporator, and a tubuluar condenser in communication with said evaporator, of a vapor delivery pipe 'between the generator-absorber and the condenser, and having its dischargeend disposed within the tubuluar condenser at a point below the connection between the condenser and the evaporator, a vapor return pipe between the evaporator and the generatorabsorber, and a connection between the vapor return pipe and the condenser for balancing the pressure in the vapor return pipe and the condenser.

4. In a refrigerating device of. the class described, the combination with a generator-absorber, an evaporator, and a tubular condenser in communication with said evaporator, of a vapor delivery pipe between the generator-absorber and the condenser, and having its discharge end disposed within the tubular condenser at a point below the connection between the condenser and the evaporator, a vapor return pipe between the evaporator and the generator-absorber, and a tubular connection between the vapor return pipe and the condenser for balancing the pressure therein, the point of communication of said connection with said vapor return pipe being in a higher plane than its point of com,- munication with the condenser.

5. In a refrigerating device of the class described, the combination with a generator-absorber, and an evaporator, of means connecting the same and dening a path for the flow' of kthe generated gases from the generator-absorber to the evaporator, and also a separate path for the iiow from the evaporator to the generator-absorber of the gases to be absorbed, said last mentioned path terminating below the liquid level of the generator-absorber, a dome mounted on the generator-absorber, a gas pipe located in said dome and in communication with the interior of the generator-absorber, a covering cap for the end of said gas pipe and serving as a barrier for the entering gases to deect their path of flow through the dome, means for maintaining a body of liquid within said dome at a predetermined height for cooperation with said closure cap to form a seal within the dome, and a connection between saiddome and the path for the ow of the generated gases from the generator-absorber to the evaporator.

6. In a refrigerating device of the class described, the combination with a generator-absorber, and an evaporator, of means connecting the same and defining a path for the flow of the generated gases from the generator-absorber to the evaporator, and also a separate path for the flow from the evaporator to the generator-absorber of the gases to be absorbed, said last mentioned path termina-ting below the liquid level of the generator-absorber, a dome mounted on the generator-absorber, a gas pipe. located in said dome and in communication with the interior of. the generator-absorber, a covering cap for the end of said gas pipe and serving as a barrier for the entering gases to deect their path of flow through the dome, a drain pipe in communication with the interior of the generator-absorber and projecting into said dome, the projecting end of said drain `pipe serving to maintain a body of liquid within said dome at a predetermined height for cooperation with said closure cap to form a seal within the dome, and a connection between said dome and the path for the flow of the generated gases from the generator-absorber to the evaporator.

7. A refrigerating device including a generator-absorber, an evaporator, the evaporator being located in a relatively higher horizontal plane than the generator-absorber, and means connecting the same and deiining paths for the flow of the generated gases from the generator-absorber to the evaporator, and also from the evaporator to the generator-absorber of the gases to be absorbed, in combination with a refrigerator cabinet including a refrigerating chamber and a storage space below the same, a common pivoted closure for said chamber and space, a mounting on said closure for the refrigerating device positioning the generator-absorber within the storage space of the cabinet and the evaporator within the refrigerating chamber thereof, and means for receiving the connecting means defining the W of the generated gases from the generator-absorber to the evaporator.

8. A refrigerating device including a generatorabsorber, an evaporator, the evaporator being located in a relatively higher horizontal plane than the generator-absorber, and means connecting the same and defining paths for the iiow of the generated gases from the generator absorber to the evaporator, and also from the evaporator to the generator-absorber of the gases to be absorbed, in combination with a refrigerator cabinet including a refrigerating chamber and a storage space below the same, a door for said cabinet closing the refrigerating chamber and the storage space, a mounting for the refrigerating device in association with said door and positioning the generator-absorber within the storage space of the cabinet and the evaporator Within the refrigerating chamber thereof when the door is closed, the cabinet having provision for receiving the connecting means defining the flow of the generateed gases from the generator-absorber to the evaporator.

9. In a refrigeratng device of the class described, the combination with a generator-absorber, an evaporator located in a relatively higher plane than the generator-absorber, and a tubular condenser having an overflow connection intermediate its ends communicating with said evaporator, of a vapor delivery pipe between the generator-absorber and the condenser, said delivery pipe having one of its ends enclosed within the condenser in spaced relation to the walls of the condenser, a vapor return pipe rbetween the evaporator and the generator-absorber having its f highest point above the condenser, and a connection between the high point of the vapor return pipe and the upper part of the condenser for balancing the pressure in the vapor return pipe and the condenser.

CLARENCE T. SORENSEN. 

